Dogs need regular exercise to burn off excess energy. If they're not getting enough physical activity, they may become restless and try to escape in search of stimulation.
Loud noises, thunderstorms, or fireworks can terrify dogs. When frightened, they may try to flee to what they perceive as a safer place.
Dogs need mental stimulation as well as physical exercise. Boredom can lead to restlessness, and they may try to escape to find something interesting to do.
Dogs are social animals and need companionship, both from humans and other dogs. If they're lonely or not receiving enough attention, they may try to escape to seek out social interactions.
If a new animal moves into the neighborhood or if there are aggressive dogs nearby, a dog might try to run away to avoid confrontation or establish a new territory.
If a dog is in an unfamiliar place, they might try to find their way back home, especially if they're scared or disoriented.
Some breeds have strong hunting instincts. They may try to chase after wildlife or scents, leading them to stray far from home.
Intact (non-neutered) male dogs may roam in search of a mate, especially during the breeding season.